The present invention relates to semiconductor processing. Specifically, the present invention relates to a process chamber lid that facilitates cleaning of an interior of the process chamber.
During chemical vapor deposition (CVD) processing, reactive gases released inside a process chamber form layers, such as silicon oxides or nitrides, on the surface of a substrate being processed. During this process, oxide/nitride deposition occurs elsewhere in the CVD apparatus. The oxide/nitride residue has a deleterious effect on the CVD process if the CVD apparatus is not periodically cleaned. To avoid these deleterious effects, periodic cleaning procedures are undertaken to remove the oxide/nitride residue every N wafers, where N is an integer. The cleaning procedures, however, result in periodic down-time for the CVD system, thereby reducing the system throughput.
To reduce the total down-time of the CVD system, due to the aforementioned cleaning procedures, two types of cleaning techniques are employed: a gas-clean technique and a wet-clean technique. During a gas-clean technique, a cleaning gas, such as oxygen, NF.sub.3, helium and/or nitrogen, is flowed into the process chamber to remove oxide residue present therein. The gas-clean technique is achieved without breaking the vacuum seal of the process chamber, the seal being formed when a lid associated with the process chamber is in a closed position. This technique minimizes the amount of down-time necessary to perform the cleaning procedure. The gas-clean technique is unable to remove a portion of the oxide residue present in the CVD system, necessitating a periodic wet-clean technique. During a wet-clean technique, the vacuum seal of the process chamber is broken by moving the chamber lid to an open position. A user physically wipes down the chamber using chemical cleaners. Thus, the wet-clean technique is substantially more time-consuming than the gas-clean technique, thereby increasing the down-time of the CVD system.
What is needed, therefore, is a CVD system that reduces the time required for cleaning.